Hash Generator

No, cryptographic hash functions are designed to be one-way and irreversible. You cannot recover the original input from a hash. This is a fundamental property of hash functions, not a bug or limitation. However, weak hashes like MD5 can be vulnerable to rainbow table attacks where pre-computed hashes are used to guess common inputs.

No, they serve different purposes. Encryption is designed to be reversible with the correct key—you can decrypt encrypted data. Hashing is one-way and irreversible. Encryption protects confidentiality, while hashing ensures integrity and is used for verification, not secrecy. Never use hash functions when you need to retrieve the original data later.

For security purposes, use SHA-256 or SHA-512. Avoid MD5 and SHA-1 as they're cryptographically broken. For general-purpose checksums where security isn't a concern, MD5 is acceptable. For password hashing, use specialized algorithms like bcrypt, scrypt, or Argon2 instead of plain hash functions. For blockchain applications, SHA-256 is the industry standard.

A hash collision occurs when two different inputs produce the same hash output. While theoretically possible due to the pigeonhole principle (infinite inputs, finite outputs), good hash functions make collisions extremely unlikely. MD5 and SHA-1 are vulnerable to collision attacks, which is why they're deprecated. SHA-256 and SHA-512 are currently collision-resistant.

Absolutely. All hash calculations are performed entirely in your browser using the Web Crypto API. No data is ever sent to our servers or any third party. You can even use this tool offline once the page is loaded. Your sensitive data remains completely private and secure on your device.

Hash functions produce fixed-size outputs regardless of input size. MD5 always produces 128 bits (32 hex characters), SHA-256 always produces 256 bits (64 hex characters), and SHA-512 always produces 512 bits (128 hex characters). This consistency makes hashes predictable and suitable for storage in databases and comparison operations.

Use HMAC when you need both integrity and authenticity verification with a shared secret key. Regular hashes verify integrity only—anyone can compute them. HMAC requires a secret key, so only parties with the key can generate valid signatures. This is essential for API authentication, message verification, and preventing tampering in untrusted environments.

While you can technically hash passwords with SHA-256, it's not recommended for production systems. Password hashing requires specialized algorithms like bcrypt, scrypt, or Argon2 that are designed to be slow and include automatic salting. This tool is best for testing, learning, or generating hashes for non-password data like file checksums and API signatures.

This tool supports plain text (UTF-8), hexadecimal strings, and Base64-encoded data as input formats. UTF-8 handles all Unicode characters including emoji and international text. For file hashing, you can paste the file content, though for large binary files, specialized tools are more appropriate. The tool automatically handles character encoding to ensure consistent results.

A salt is random data added to passwords before hashing to defend against rainbow table attacks and prevent identical passwords from producing identical hashes. Each user gets a unique salt stored alongside their hash. This means attackers must compute rainbow tables for each salt, making pre-computed attacks impractical. Salting is crucial for password security but isn't needed for checksums or file verification.